Remember the orphaned hippo and the tortoise?

You know what they say about best friends: how after a while they start acting just like one another? That's what's happening with one of the planet's most unlikely pairs, Owen and Mzee. And it has conservationists worried.

The baby hippo and giant tortoise have developed their own way of talking to one another. Experts at Mombassa wildlife sanctuary say it's the first time they've seen a mammal and a reptile chatting

Owen is a young hippo who was separated from his herd after last year's tsunami and stranded on a coral reef off the coast of Kenya. He was rescued and placed in the Haller Park wildlife sanctuary in Mombasa. There, he quickly befriended Mzee, a 130-year-old giant tortoise.

Dr Paula Kahumbu said: "We discovered that somebody was making a sound in the pen, we'd never heard it before, not even from other hippos. "And then we realised it was coming from both Owen and Mzee... It's just very unusual."

Conservationists think Owen may have cuddled up to the Mzee on his first night at the sanctuary because the tortoise's colour and shape were similar to the hippo's. Now, a year later, the pair is inseparable. They spend their days wallowing together, nudge one another to go for walks, and sleep beside each other at night. They even seem to be communicating, making soft, high-pitched whimpering sounds to each other that are completely unlike the hisses and grunts of tortoise calls or the honking of hippos.

Owen, who weighed an estimated 660 pounds (300 kilograms) when he arrived at the park, was two-thirds the size of Mzee. He is now twice Mzee's size and still growing

Clearly, the friendship has changed them both. Owen sleeps at night rather than during the day, eats tortoise food, and doesn't respond to hippo calls. And the tortoise, which is not an affectionate or social animal, seems genuinely attached to the young hippo.

"He will grow to anywhere between three and four tons—he's gonna be a big male hippopotamus," said Paula Kahumbu, the general manager of Lafarge Ecosystems, the Kenyan environmental restoration firm that manages the wildlife sanctuary

So why break up the friendship?

The problem is Owen's size. When he arrived, he was 300 kilograms—about two thirds Mzee's weight. Now he's twice Mzee's size and playful. Owen will eventually weigh between three and four tons, and conservationists are worried he'll accidentally hurt the slow-moving tortoise.

"He's already quite playful, already quite strong," she said. "He could injure Mzee at any moment. He's very childlike in his behavior. As he gets older he will get rougher. Mzee is not a flexible animal—he could be injured"

That's why they're hoping Cleo, a female hippo, will come between the pair.

While other tortoises, monkeys, and antelope roam in that enclosure, Mzee has shown no affection toward any of them

Conservationists plan to move Owen and Mzee to a new enclosure, then introduce Cleo. If Owen and Cleo bond, they'll live together in the hippos-only enclosure. Mzee will be moved back to the safety of his old grounds with other tortoises.

Conservationists hope to introduce a 13-year-old female hippo to Owen and that the two will bond with no objection from the tortoise

The question is just how much the friendship has changed them; whether Owen will take to the company of another hippo and whether Mzee will be traumatized by the separation from his friend.

Owen seems to be getting used to the new tortoise in his enclosure. Although he follows him around and spends time in the water with him, he does not treat him the same way that he would normally treat Mzee. Owen often pushes Mzee to get him to move along and normally is not found away from Mzee for long lengths of time. But he does not do this with the new tortoise

The experiment will show whether the bonds of friendship really have changed these two irrevocably, for better or for worse.

Source: National Geographic

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